The problem with proportional representation and list is exactly what happens in Israel - there are single-issue parties where the voters who adhere to that party line care very little about anything except the obsession of the party brass. Imagine the same system in the USA, there would be an “Anti-Abortion Party” that would probably siphon about 10% to 20% of the votes from the conservative side, and an “Occupy Wall Street” or “Universal Health Care” party on the left, and perhaps Black Power or Latino parties which might capture enough of those voters to get a few seats. (How else do you explain Green Party, or Ralph Nader?) Meanwhile, the people on the list for each party achieve their position and jockey to move up the list by sucking up to the party brass rather than listening to constituents; the MP’s are party political hacks, not locally prominent and locally known representatives. Local issues are minor to them. Attracting voters in the big boss’s job. The smaller parties drive a hard bargain because that’s what their overly-committed constituents want. This is a recipe for gridlock. Government certainly cannot make longer term unpopular but necessary decisions, which is the downside of minority government.
That is why the negotiations in some countries can go on for weeks and months - think of the current border wall dispute, but with five different small parties with five different make-or-break demands, all holding out and knowing one or the other major party must give in to get their support. (The American system is the same, but with 430 individual parties and repeat negotiations on each piece of legislation…)
First past the post is a crappy system, but generally it emphasises the national consensus.
One would hope that in that situation, the PM would have time to call in the leaders of the other major parties to try to find common ground on that particular issue (and if necessary a “grand coalition” or all-party national government, as in WW2).
Has there ever been a British PM who has filled the role on a caretaker basis? I can’t think of one, although I can think of a present-day scenario where one might be appointed.
It’s really unlikely though:
the government loses a no-confidence vote and thus has 14 days to cobble together something or else there’s a General Election
no deal is reached and so a GE is called. This means that all MPs are no longer MPs, although in-situ Ministers retain their responsibilities for the five weeks a GE campaign takes
the sitting PM dies
Her Maj consults with the Privy Council and appoints a respected elder statesperson to hold the fort until the GE result is known, perhaps someone from the House of Lords
(and then nuclear hell is unleashed! Feel free to steal this scenario for your novel, Elendil’s Heir )
On a technicality the incumbent PM goes into caretaker mode each time parliament is dissolved for a general election until the new government is sworn in. Is purdah the term used in Britain?
Apart from the election period Australia has had three caretaker governments since Federation (1901 and 1914 and 1975) but only in 1975 was the caretaker not the incumbent.
)